Bookbinding

ABSTRACT

A stack of printed sheets, ready for binding, is formed with a plurality of grooves across the edge thereof to be bound. An elastic member, formed with a like plurality of projecting ridges, is subjected to a force which contracts the ridges to a size sufficient to enable them to be fitted within the grooves. Upon removal of the force from the elastic member, the ridges revert toward their original configuration causing them to be lodged within the grooves thereby securing the stack of sheets as an assemblage.

United States Patent Schlieben [451 Aug. 22, 1972 BOOKBINDING [72]Inventor: Ernest William Schlieben, Morrisville, Pa.

[73] Assignee: RCA Corporation [22] Filed: Sept. 19, 1969 [21] App].No.: 859,508

[52] US. Cl. ..281/26, 402/8, 402/19, 402/80 R, 402/501 [51] Int. Cl...B42b 5/00 [58] Field of Search ..281/26, 23, 28, 36, 17, 16; 402/8,9,10,l1,13,l5,l9, 80,12,14, 501

[56] References Cited UNITED STATES PATENTS 268,407 12/1882 Hughes..24/l30 UX 1,778,490 10/1930 Grammer ..281/26 2,258,874 10/1941Williams ..281/26 2,297,958 10/1942 Hauel ..402/8 FOREIGN PATENTS ORAPPLICATIONS 752,929 7/1933 France ..402/15 285,306 2/ 1928 GreatBritain ..281/26 Primary Examiner-Jerome Schnall Alt0rney-Edward J.Norton ABSTRACT A stack of printed sheets, ready for binding, is formedwith a plurality of grooves across the edge thereof to be bound. Anelastic member, formed with a like plurality of projecting ridges, issubjected to a force which contracts the ridges to a size sufficient toenable them to be fitted within the grooves. Upon removal of the forcefrom the elastic member, the ridges revert toward their originalconfiguration causing them to be lodged within the grooves therebysecuring the stack of sheets as an assemblage.

2 Claims, 7 Drawing Figures PATENTED 1922 1972 3.685, 857

INVEN TOR.

g4 E RNEST W5 555,

- QQZW ArrorLuEY BOOKBINDING This invention relates to techniques forbinding, in book form, stacked sheets of paper or the like.

The art of bookbinding has made little progress from the time of itsinception to the present. Traditionally, bookbinding techniques haveincluded time consuming sewing steps, as well as messy gluingoperations, to bind together a stack of printed sheets between a pair ofbook covers. The rising cost of labor, coupled with the desirability ofefficient high speed production, has dictated the necessity for thedevelopment of more modern techniques.

Accordingly, it is an object of the present invention to provide aneconomical and efiicient method for binding books and the like.

A further object is to provide a novel article of manufacture suitablefor use in conjunction with the method of the present invention.

A method of binding an edge of a stack of paper sheets or the like intobook form, in accordance with the present invention, comprises the stepsof forming said edge with a plurality of grooves; aligning said grooveswith a member formed with a like plurality of ridges, said member beingmade of an elastic material, the cross sectional area of said ridgesbeing normally greater than the cross sectional area of said grooveswhen said elastic member is in a relaxed state; applying a force to saidelastic member to cause contraction of the cross sectional area of saidridges; inserting the contracted ridges of said member into the groovesformed within said stack; and removing the force from said elasticmember to permit said ridges to expand and lodge within said groovesthereby securing said member to said stack.

An article of manufacture suitable for use in conjunction with themethod of the present invention, for example the method as set forthsupra, comprises a sheet of material formed with a like plurality ofprotruding ridges, the cross sectional configuration of said ridgesbeing normally larger than the cross sectional configuration of saidgrooves, said material having a coefiicient of elasticity which respondsto the application of a force in a direction parallel with thelongitudinal axes of said ridges to cause the cross sectionalconfiguration thereof to decrease and permit its insertion within saidgrooves and which, upon the removal of said force, will permit the crosssectional configuration thereof to increase and lodge said ridges withinsaid grooves.

The present invention, as well as additional objects and advantagesthereof, will be best understood upon reading the following descriptionin conjunction with the accompanying drawing wherein:

FIG. 1 is illustrative of a stack of paper sheets prepared for bindingin accordance with the present invention;

FIGS. la and lb are enlarged views of the inserts depicted in FIG. 1 andillustrate groove configurations in accordance with preferredembodiments of the present invention; FIG. 2 is illustrative of anelastic member suitable for use in accordance with the method of thepresent invention and depicts an embodiment of the article ofmanufacture in accordance therewith;

FIG. 3a is an isometric sectional view of the ridges shown in FIG. 2 inthe absence of the applied force F as shown therein;

FIG. 3b is an isometric sectional view of the ridges shown in FIG. 2when said elastic member is subjected to the applied force F as showntherein; and

FIG. 4 is a sectional view of the elastic member as shown in FIG. 2 andincludes an exterior cover as well as a backing strip for the boundedge.

As discussed supra, bookbinding techniques have traditionally includedmany separate manufacturing operations and required many different kindsof materials; e.g. leather, cloth, thread, glue, sizing, etc.Furthermore the quality of the resulting product has proven to be ofvarying durability, particularly in the case of low cost books andcatalogues where only gluing techniques are relied upon to maintain theintegrity of the binding.

The present invention recognizes the antiquity of traditionalbookbinding techniques and, in place of costly sewing and gluingoperations, proposes the use of a novel binding technique whichincorporates a preformed member made of an elastic material.

The applicability of plastics technology to bookbinding techniques hasbeen recognized, to some degree, by the prior art; see for example U.S.Pat. Nos. 2,258,874, 2,355,737 and 2,579,488. Generally, in the priorart techniques, the edge of a stack of sheets of paper to be bound isdisposed within the cavity of a mold in which liquid plastic isinserted, under heat and pressure. Upon cooling, the solidified plasticprovides a substantially rigid backbone configuration for the boundedge. Such techniques, though operable, have proven to be costly toinstitute and maintain, and impractical in operation since the moldingtakes place in direct contact with the printed sheets and often causesdamage thereto by virtue of paper burning or plastic smearing thereon.Furthermore, those skilled in the art of bookbinding generally havelittle if any knowledge in the art of handling liquid plastic.

As shown in FIG. 1, the present invention requires that the printedsheets 10 be stacked and aligned, and a plurality of grooves 12 formedin the edge 14 thereof to be bound. As shown in FIGS. la and 1b, thecross section of the grooves 12 may vary in shape and, in accordancewith a preferred embodiment of the present invention, the grooves areformed with a restricted entrance at their upper surface 13. A preformedmember 20 formed with protruding ridges 22, as shown in FIG. 2, is thenbrought into relative proximity with the grooved edge 14 of theassembled stack 10; the ridges 22 upon the member 20 correspond innumber to the grooves within said edge. The cover member 20 may beformed of an elastomer or high polymer plastic material having arelatively high coefficient of elasticity; for example, polurethane orpolyvinyl butyrate. Although it may prove desirable to configure theridges 22 to conform to the shape of the grooves 12, e.g. as shown inFIGS. la and 1b, such conformation is not necessary. The ridges areconfigured, however, such that they are denied access to the grooves 12,when in a relaxed state.

FIG. 3a depicts, in cross sectional isometric view, the configuration ofridges 22 which may be used in conjunction with the grooves 12 shown inFIG. 10. When a force F is exerted transverse to the cross sectionalarea of the ridges 22, as shown in FIG. 2, they are caused to contractin cross section, while increasing in length and height, as shown inFIG. 3b. While in a contracted state they may be fitted within thegrooves 12, readily entering the restricted access portions 13. Uponrelease of the transverse force F the ridges 22 revert toward theiroriginal configuration due to the elasticity of the material used,causing them to lodge within the grooves 12 in a substantially rigidmanner, thereby preventing the individual sheets from separating fromthe stacked assembly. a

In the embodiment represented by FIGS. 2 and 4, the member 20 isdepicted as a unitary sheet having ridges 22 formed in a middle portionthereof. In this embodiment, the portions 24 of the sheet not containingridges 22 may be folded over (not shown) to form the cover portions ofthe book. Moreover, if desired, a rigid and/or ornamental cover 40 maybe afiixed to said folded portion 24 of the member 20. The outer cover40, for example, may be ofcloth or leather to provide a more decorativeeffect. A backing strip 42 containing the title and/or author, etc.could then be affixed to the bound edge.

Alternatively, it may be desirable to form the member 20 with a widthsubstantially equal to the length of the ridges 22. In such event, themember would thereafter be affixed to a cover member which wouldsubsequently be folded about the bound pages.

What is claimed is:

l. A method of interconnecting a stack of sheets at an edge thereofcomprising the steps of:

a. forming said edge with a plurality of elongated recesses, each recessbeing shaped to interlock with a complementary projection insertedtherein,

b. aligning said recesses with a plurality of interlocking projectionswhich are like in number and complementary in shape to said recesses andwhich are formed from and integral with an elastic member said elasticmember having portions extending beyond opposite ends of saidprojections, each projection corresponding to a separate differentrecess, the shape of each of said projections tending to prevent theinsertion thereof into the corresponding recess,

applying said force to said member in a direction different than saidnormal direction. 2. The method of claim 1 wherein a cross sectionalarea of each projection is normally reater than the complementary crosssectional area 0 the corresponding recess when said member is in arelaxed state, said a force applying step including the step of applyinga force to said elastic member to resiliently reduce said crosssectional area of each of said projections to a value less than thevalue of said complementary cross sectional area of said correspondingrecesses, said inserted projections being resiliently compressed againstsaid stack when said reducing force is removedto thereby closely securesaid member to said stack.

. applying a force to said extending portions of said

1. A method of interconnecting a stack of sheets at an edge thereofcomprising the steps of: a. forming said edge with a plurality ofelongated recesses, each recess being shaped to interlock with acomplementary projection inserted therein, b. aligning said recesseswith a plurality of interlocking projections which are like in numberand complementary in shape to said recesses and which are formed fromand integral with an elastic member, said elastic member having portionsextending beyond opposite ends of said projections, each projectioncorresponding to a separate different recess, the shape of each of saidprojections tending to prevent the insertion thereof into thecorresponding recess, c. applying a force to said extending portions ofsaid elastic member to resiliently distort the shape of said projectionsto permit their insertion into said recesses, d. inserting the distortedprojections into their respective, corresponding recesses, and e.removing the force from said elastic member to cause said projections tosubstantially assume said inter-lock shape to thereby secure said memberto said stack said recesses being grooves extending substantiallyparallel with respect to each other through all of said sheets, saidinserting step including inserting said projections in a directionsubstantially normal to said grooves, and said force applying stepincluding applying said force to said member in a direction differentthan said normal direction.
 2. The method of claim 1 wherein a crosssectional area of each projection is normally greater than thecomplementary cross sectional area of the corresponding recess when saidmember is in a relaxed state, said force applying step including thestep of applying a force to said elastic member to resiliently reducesaid cross sectional area of each of said projections to a value lessthan the value of said complementary cross sectional area of saidcorresponding recesses, said inserted projections being resilientlycompressed against said stack when said reducing force is removed tothereby closely secure said member to said stack.